Transcript Slide 1
Anti predator behaviors: Adaptive behaviors that: •Are typically specialized to the details of predator prey interaction •Can be associated with special physiological changes •Typically based on ecological constraints Evolutionary principles: •Adaptation: a trait that infers (or at one time inferred) an advantage •Convergent evolution: The independent evolution of a common solution •Divergent evolution: Unique evolutionary solutions Mobbing behavior: does it take a mob to mob? The purpose of mobbing behavior is to disrupt predatory action. Mocking bird mobbing red-tailed hawk Fairy terns mobbing Black kite Mobbing behavior: does it take a mob to mob? Eurasian marsh harriers prey on carrion crows Carrion crows will individually mob eurasian marsh harrier Other parental behaviors that disrupt predatory action. Ptarmigans, like many birds will fain injuries and lead predators away from the nest The evolution of mobbing behavior Could mobbing behavior have evolved: •before gulls split from other bird taxa? •as a non social parental defense trait that emerges as a mob act under conditions of expression in flocking species? Does mobbing behavior provide an advantage? Cryptic behavior: If you can’t see it you can’t eat it The evolution of specialized structural adaptations still requires adaptive behavior to pull off the illusion moths resembles a dead leafs on the forest simulated leaf veins running through wingtips Moths also must be selective of where they hide and how they orient. The evolution of specialized structural adaptations still requires adaptive behavior to pull off the illusion The motionless twig caterpillar shown here (courtesy of Muriel V. Williams) complete with "buds" and "lenticels" escapes detection by birds. In the lowland rain forest of the Peruvian Amazon, "bird dropping caterpillar.” The evolution of specialized structural adaptations still requires adaptive behavior to pull off the illusion Cryptic mimicry in the katydid Cryptic coloration and behaviors in amphibians/reptilians How Many animals in these pictures? Cryptic coloration and behaviors in Fishes Advertising bad food quality: Bright colors elaborate decor •The caterpillar of an Io moth has sharp and toxic urticating spines. The spines are called •Such honest signaling is an alternative to mimicry. The Io moth as an adult reverts to eyespots on its hind wings, which it displays when threatened. Come on: I dare you! Golden poison frog Phantasmal poison frog Yellow-banded Poison Frog Blue poison frog Red spotted arrow frog Dyeing poison frog Batesian Mimicry in insects: False advertising Real species fakes Batesian mimicry: Cryptic imposters This edible insect nymph assumes the fraudulent guise of a stinging ant in both appearance and behavior. Batesian mimicry in moth larvae Camouflage: Decorator crabs place chemically defended seaweeds on their backs, attaching them via hooked setae on their carapace. This strategy works to reduce predation because this seaweed is distasteful to omnivorous consumers that eat both seaweeds and small invertebrates like crabs But don’t eat it Like to wear it Camo: its not just for prey! Camo: its not just for prey! •A scorpionfish lies immobile on a coral reef. •Its crypsis serves to keep it hidden from prey. mimicry: its not just for prey either! Mimicry in predators Some carnivores have evolved devices with which they mimic prey (or potential mate) of other (usually smaller) predators. They use these devices as lures. The angler fish (Antennarius) displays a lure resembling a small fish. The lure is a development of the spine of the first dorsal fin. This species of anglerfish, which was found in the Philippines, is 9.5 cm long. Note its use of camouflage: its texture (and color) closely resemble the sponge- and algae-encrusted rocks found in its habitat.